15. For the purpose of these Regulations, subject to paragraph 17–
“Part A installation” means an installation where a Part A activity is carried out (including such an installation where a Part B or Part C activity is also carried out);
“Part B installation” means an installation where a Part B activity is carried out, not being a Part A installation (including such an installation where a Part C activity is also carried out);
“Part C installation” means an installation where a Part C activity is carried out, not being a Part A installation or Part B installation.
16. For the purpose of these Regulations–
“Part A mobile plant” means mobile plant used to carry out a Part A activity (including such plant which is also used to carry out a Part B or Part C activity);
“Part B mobile plant” means mobile plant used to carry out a Part B activity, not being Part A mobile plant;
“Part C mobile plant” means mobile plant used to carry out a Part C activity, not being Part A mobile plant or Part B mobile plant.
17. A Part C installation where an activity within Part C of Section 1.1 is carried out does not include any location where the associated storage, handling or shredding of tyres which are to be burned as part of that activity is carried out.
18. A Part B installation where an activity falling within paragraph (a) of Part B of Section 2.2, or a Part C installation where an activity falling within paragraph (c) of Part C of Section 2.2 is carried out does not include any location where the associated storage or handling of scrap which is to be heated as part of that activity is carried out, other than a location where scrap is loaded into a furnace.
19. A Part B installation where an activity falling with paragraph (a) or (b) of Part B of Section 5.1 or a Part C installation where an activity falling with paragraph (a) or (b) of Part C of Section 5.1 is carried out does not include any location where the associated storage or handling of wastes and residues which are to be incinerated as part of that activity is carried out, other than a location where the associated storage or handling of animal remains intended for burning in an incinerator used wholly or mainly for the incineration of such remains or residues from the burning of such remains in such an incinerator is carried out.
20. A Part B or Part C installation where an activity falling within Part B or Part C of Section 6.4 is carried out does not include any location where the associated cleaning of used storage drums prior to painting or their incidental handling in connection with such cleaning is carried out.
21. Where an installation is a Part A installation, a Part B installation or a Part C installation by virtue of the carrying out of an activity which is only carried out during part of a year that installation shall not cease to be such an installation during the parts of the year when that activity is not being carried out.
22. Where an installation is authorised by a permit granted under these Regulations to carry out Part A activities, Part B activities or Part C activities which are described in Part 1 by reference to a threshold (whether in terms of capacity or otherwise), the installation shall not cease to be a Part A installation, a Part B installation, or a Part C installation, as the case may be, by virtue of the installation being operated below the relevant threshold unless the permit ceases to have effect in accordance with these Regulations.
23. In this Part, “Part A activity”, “Part B activity” and “Part C activity” have the meaning given by paragraph 11 in Part 2 of this Schedule.